The map may have instructions on either the DeviantArt/forum topic, or a readme file inside the zip/rar. I'm not sure that any of the existing map installation tutorials are outdated.
If the map has more files than .fhm, .fho, and .txt...
The images usually belong in "FeralHeart/media/terrains/textures".
The material files belong in "FeralHeart/media/materials".
I think the .sky files go into "FeralHeart/media/sky".
The .mp3 files belong in either "FeralHeart/media/sounds" or "FeralHeart/media/music", the tutorial that came with the map usually says where to put .mp3 files, but you can put mp3 files in both of those folders if the tutorial that came with the map is gone or doesn't specify where to put them.